1. Field of the Invention
The invention relates to a display apparatus, and more particularly, to a display apparatus having a better display quality.
2. Description of Related Art
With the development of flat panel display technology, liquid crystal displays (LCD) have increasingly become the mainstream of display technology, and have replaced conventional cathode ray tubes (CRT) for being widely used in daily life. Since a liquid crystal panel in the LCD cannot emit light, a backlight module is required to provide a backlight source. According to a placement position of a light emitting device, the backlight module may be divided into a direct type backlight module and a side type backlight module, wherein the side type backlight module is capable of guiding light from a side surface to a front side to form a surface light source by having a light guide plate.
In the side type backlight module, the light emitting device, for example, a cold cathode fluorescent lamp (CCFL), is disposed on a light incident surface on a side edge of the light guide plate. After passing through the light incident surface and entering the light guide plate, light from the CCFL is converted into the surface light source by the light guide plate, and is output from the light guide plate via an upper surface of the light guide plate. With breakthroughs in manufacturing technology, a light emitting diode (LED) increasingly replaces the CCFL to be used as the light emitting device in the backlight module. In prior art designs, a plurality of LEDs is arranged beside the light incident surface of the light guide plate with intervals. However, as a point light source, the light intensity of the plurality of LEDs on the light incident surface is not uniformly distributed, wherein bright regions are formed on positions corresponding to the LEDs, and a dark region is formed between two LEDs, so that the surface light source output by the light guide plate generates mura along an extending direction of the upper surface. In other words, conventionally, during practical application, the side type backlight module employing the LED as the light emitting device has a problem of non-uniform light emergence, thereby relatively lowering display quality of the LCD.